Trays for the display of packaged merchandise are well known and widely used. An example of such trays is shown in U.S. Pat. No. 6,866,155, illustrating a tray formed mostly of wire and having width-adjustable side wires for the lateral confinement of packages. A spring-operated pusher is positioned behind a column of packages and continually urges them forward. When a customer removes a package from the front of the tray, the entire column of packages is automatically moved forward by the pusher in order to keep a package at all time in a frontmost position, where it can easily be seen and removed by a subsequent customer.
While wire-sided trays, such as represented in the above-mentioned '155 patent are simple and inexpensive, and very efficient for the display of hard packages, such as boxes, cans, bottles and the like, they can be less than ideal for certain soft packages, such as bags, which can project laterally through the wide open side areas of their side wire confinements. For soft packages, it is often desirable to provide trays with panel side walls. An example of such a tray is shown in U.S. Pat. No. 8,210,367. The tray illustrated in the '367 patent has width adjustable side wall panels that are formed of flat metal, typically steel, which can fully confine the lower portions of soft packages. Trays with metal side walls may sometimes be required, as where the side walls provide cantilever support for the trays. In other cases, as where the trays are supported on store shelves, trays with panel side walls are less desirable, unless required for the display of soft packages, because they are more costly and also reduce the visibility of the displayed products. Accordingly, there is a need for product display trays of the types above described, which can be provided with the preferred open wire side confinement while at the same time being easily and quickly converted to panel-sided trays, if necessary, or desirable for the display of soft packages.